Thanks; I did think of the hire shop option, but none of those in my area (and that includes all the usual Jewson/HSS/Speedy etc) have anything listed. What would you suggest I ask for?
I have a patio built up to a low herb bed wall on 2 sides on the lower edge of the area, so in a heavy rainfall we get standing water up to about half way across the area - the wall makes a very effective dam! The fact that the patio is made of natural sandstone with a riven face doesn't help...